itsa基 31 過半元素

#include<iostream>
#include<string>
#include<sstream>
using namespace std;

int main()
{
int arr[30];
int N, count,a;
string str;
while (getline(cin, str))
{
a = 0;
N = 0;
stringstream ss(str);
while (ss >> arr[N++])
{

}
N--;
for (int i = 0; i < N; i++)
{
count = 0;
for (int j = 0; j < N; j++)
{
if (arr[i] == arr[j])
count++;
}
if (count > N / 2)
{
a = 1;
cout << arr[i] << endl;
break;
}
}
if (count <= N / 2 && a == 0)
cout << "NO" << endl;
}
return 0;
}